Research to Test Whether the Restorative Hypothesis of Sleep is a Useful Predictor of the Effects of Sleep on Memory of Meaningful Concepts
There has been speculation for a very long time that sleep is beneficial in aiding memory. The seminal study by Jenkins and Dallenbach (1924) apparently showed a clear correlation between sleep and enhancement of memory. However, as pointed out by Idzikowski (1984), this research does not show whether the memory enhancement was due to sleep or to the fact that a night had passed. In other words, the two factors, sleep and night, were confounded in this experiment.